Methods and apparatus are provided for securely blocking and sealing an access corridor to a secure facility. The exemplary system includes a penetration resistant door disposed in a passage intersecting the access corridor, and dividing it into first and second sides. An actuating mechanism translates the door within the passage between an open position in which the corridor is unblocked, and a closed position in which the corridor is blocked by the door. A locking system is configured to push the door toward one side of the access corridor when the door is in the closed position, compressing a seal disposed between the door and the passage wall, and sealing the first side of the access corridor from the second side.
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23. A method for securing and sealing an access corridor to a high security facility, comprising the steps of:
providing a passage that intersects the access corridor, delineating a first side of the access corridor on one side of the passage, and a second side of the access corridor on the other side of the passage;
blocking the passage with a penetration resistant door, wherein a front surface of the door faces a front wall of the passage and the first side of the access corridor, and a back side of the door faces a back wall of the passage and the second side of the access corridor;
pushing the door toward the front wall of the access corridor using a locking system that drives a bolt against the perimeter portion of the door, the bolt engaging a socket in the door;
bracing the bolt against the back wall of the passage; and
sealing the access corridor with a compressible seal disposed between the door and the front wall of the passage.
1. An apparatus for securing an access corridor to a high security facility, comprising:
a door passage intersecting the access corridor, and delineating a secure side of the access corridor on one side of the door passage, and a threat side of the access corridor on the other side of the door passage;
a penetration resistant door disposed within the passage, and oriented with a front surface of the door facing a front wall of the passage and the threat side of the access corridor, and a back side of the door facing a back wall of the passage and the secure side of the access corridor;
a system for translating the door within the door passage between an open position in which the access corridor is unblocked, and a closed position in which the door blocks the access corridor, the perimeter of the door extending into the passage beyond the walls of the corridor in the closed position; and
a locking system in the passage configured to push the door toward the front wall of the passage, the locking system comprising at least two actuated bolts, sockets in the door configured to receive an end of the bolts, and a shim stack between the ends of the bolts and the door.
20. An apparatus for securing an access corridor to a high security facility, comprising:
a door passage intersecting the access corridor, and delineating a secure side of the access corridor on one side of the door passage, and a threat side of the access corridor on the other side of the door passage;
a penetration resistant door disposed within the passage, and oriented with a front surface of the door facing a front wall of the passage and the threat side of the access corridor, and a back side of the door facing a back wall of the passage and the secure side of the access corridor;
a system for translating the door within the door passage between an open position in which the access corridor is unblocked, and a closed position in which the door blocks the access corridor, wherein the door translates vertically within the passage, and the perimeter of the door extends into the passage beyond the walls of the corridor in the closed position;
a locking system in the passage configured to push the door toward the front wall of the passage;
compliant door guides extending from the door and configured to contact the walls of the passage, the compliant door guides each comprising a rolling element biased against the wall of the passage, wherein the rolling element comprises a cylindrical roller supported on a shaft held in a bracket oriented to roll in a vertical direction along the walls of the passage; and
wherein the door guides in contact with the side walls of the passage comprise a bracket substantially wider than the cylindrical roller, and a spring disposed about the shaft between the roller and one side of the bracket biasing the roller to the other side of the bracket.
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The present invention generally relates to doors used in high security facilities, and more particularly relates to a blast door system with a secure arrangement for locking and sealing the door against explosive events and leakage of hazardous materials.
Blast resistant doors are typically employed in military and industrial facilities where there exists the potential for an explosion and the release of hazardous or noxious materials, such as for example material storage rooms, laboratories, research facilities, ammunition depots, military facilities, and other high security installations. In such facilities, the doors are generally designed in anticipation of a breaching explosion occurring either within the facility, such as would occur from an accidental explosion of the contents of the facility, or outside the facility, such as from an intentionally directed explosive attack by an intruder or terrorist. Various sealing schemes are incorporated to prevent leakage of dangerous materials and gases from occurring in such events. Typically an overlapping arrangement is used, with the blast door designed to close against the side of the facility (i.e. inside or outside) facing the anticipated explosive event. The pressure pulse from an explosive event thus acts in the direction of closing the door, tending to compress the door against the facility and enhance the sealing effect.
However, in some applications there is a need for a blast door capable of maintaining a seal when exposed to explosions or attacks occurring on either side of the door. For example, certain high security installations employ two blast doors to create a Sally Port intended to contain and seal against explosions occurring either within the facility, or within the Sally Port. Similarly, it may be very advantageous for the doors of an ammunition depot to be capable of withstanding an accidental explosion within the facility, as well as a hostile explosive attack from the outside. In such applications the conventional overlapping door arrangement has unavoidable disadvantages from the standpoint of both security and maintaining integrity of the seal.
From the standpoint of maintaining seal integrity, the door overlap is beneficial in one direction, but generally detrimental in the other direction, providing no inherent resistance against pressure applied to the non-overlapping side of the door. In particular, pressure against the non-overlapping side tends to move the door away from the facility wall rather than toward it, thus weakening or releasing the seal.
From a security standpoint, because the pressure pulse is not being transferred to the facility, the entire load is typically carried by the door latching and bolting mechanisms. The resulting loads can produce excessive shear and tensile stresses in these mechanisms and in the fasteners retaining them to the facility structure. Once weakened, they become more vulnerable to further attacks.
Accordingly, a need exists for a sealable, blast resistant door capable of withstanding an explosive pressure load against either side of the door without degradation of the seal. A further need exists for a blast resistant door with a more robust latching and locking design.
Various exemplary embodiments of the present invention are described below. Use of the term “exemplary” means illustrative or by way of example only, and any reference herein to “the invention” is not intended to restrict or limit the invention to exact features or steps of any one or more of the exemplary embodiments disclosed in the present specification. References to “exemplary embodiment,” “one embodiment,” “an embodiment,” “various embodiments,” and the like, may indicate that the embodiment(s) of the invention so described may include a particular feature, structure, or characteristic, but not every embodiment necessarily includes the particular feature, structure, or characteristic. Further, repeated use of the phrase “in one embodiment,” or “in an exemplary embodiment” does not necessarily refer to the same embodiment, although it may.
It is also noted that terms like “preferably”, “commonly”, and “typically” are not utilized herein to limit the scope of the claimed invention or to imply that certain features are critical, essential, or even important to the structure or function of the claimed invention. Rather, these terms are merely intended to highlight alternative or additional features that may or may not be utilized in a particular embodiment of the present invention.
According to one exemplary embodiment, the present disclosure comprises an apparatus for securing an access corridor to a high security enclosure. The exemplary apparatus comprises a passage intersecting the access corridor, and delineating a secure side of the access corridor on one side of the passage, and a threat side of the access corridor on the other side of the passage. Disposed within the passage is a penetration resistant door oriented with a front surface of the door facing a front wall of the passage and the threat side of the access corridor, and a back side of the door facing a back wall of the passage and the secure side of the access corridor. The apparatus further comprises a system for translating the door within the door passage from an open position in which the access corridor is unblocked, to a closed position in which the door blocks the corridor. The door is dimensionally larger than the access corridor such that in the closed position the perimeter of the door extends into the passage beyond the walls of the corridor. A locking system in the passage outside the corridor is configured to push the door against the front wall of the passage.
In another embodiment, the apparatus further comprises a compressible seal disposed between the door and the front wall of the access corridor.
According to another exemplary embodiment, a method is provided for securing and sealing an access corridor to a high security facility. The method includes the step of providing a passage intersecting the access corridor, delineating a secure side of the access corridor on one side of the passage, and a threat side of the access corridor on the other side of the passage. The method further includes the step of blocking the passage with a penetration resistant door, wherein a front side of the door faces a front wall of the passage and the threat side of the access corridor, and a back side of the door faces a back wall of the passage and the secure side of the access corridor. The method further comprises pushing the door toward the access corridor, and sealing the door with a compressible seal disposed between the perimeter portion of the door and a wall of the passage.
In another embodiment the method may further comprise translating the door from an open position in which the access corridor is unblocked, to a closed position in which the door blocks the access corridor.
Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.
The present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein:
The present invention is described more fully hereinafter with reference to the accompanying drawings and/or photographs, in which one or more exemplary embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be operative, enabling, and complete. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention. Moreover, many embodiments, such as adaptations, variations, modifications, and equivalent arrangements, will be implicitly disclosed by the embodiments described herein and fall within the scope of the present invention.
Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. Unless otherwise expressly defined herein, such terms are intended to be given their broad ordinary and customary meaning not inconsistent with that applicable in the relevant industry and without restriction to any specific embodiment hereinafter described. As used herein, the article “a” is intended to include one or more items. Where only one item is intended, the term “one”, “single”, or similar language is used. When used herein to join a list of items, the term “or” denotes at least one of the items, but does not exclude a plurality of items of the list.
For exemplary methods or processes of the invention, the sequence and/or arrangement of steps described herein are illustrative and not restrictive. Accordingly, it should be understood that, although steps of various processes or methods may be shown and described as being in a sequence or temporal arrangement, the steps of any such processes or methods are not limited to being carried out in any particular sequence or arrangement, absent an indication otherwise. Indeed, the steps in such processes or methods generally may be carried out in various different sequences and arrangements while still falling within the scope of the present invention.
Additionally, any references to advantages, benefits, unexpected results, or operability of the present invention are not intended as an affirmation that the invention has been previously reduced to practice or that any testing has been performed. Likewise, unless stated otherwise, use of verbs in the past tense (present perfect or preterit) is not intended to indicate or imply that the invention has been previously reduced to practice or that any testing has been performed.
The present invention comprises generally a translating security door and system for blocking and sealing off an access corridor of a high security facility. Referring now to the drawing figures, a translating door in accordance with the invention may be a door that moves vertically up and down, an example of which is shown in
For convenience, certain conventions will be used throughout to reference directions and orientations. With respect to the coordinate directions indicated on the drawings, the plus z direction is “upward”; the minus z direction is “downward”; the plus x direction is “forward”; the minus x direction is “rearward” or “backward”; and the y direction is “lateral” or “sideways”. With respect to orientations, the “front” faces forward; the “back” faces rearward; the “right side” faces in the plus y direction; the “left side” faces in the minus y direction; the “top” faces upward; and the “bottom” faces downward.
Vertically Translating Door Embodiment
In one preferred embodiment illustrated in
It should be understood that the system of the present invention is not limited to the relative location of the “threat” side of the corridor to the door system as described and depicted in the drawings. Indeed, the door system of the present invention may be suitably and advantageously employed in situations where a toxic or explosive threat is anticipated on either side, or on both sides of the door. Thus the terms “threat” and “secure” are used herein merely for reference purposes, with the intent of simply differentiating between “first” and “second” sides.
Returning to
Door 1 may be a high strength, heavily armored panel designed to resist directed, sophisticated explosive attacks. When in the closed position of
Door guides 9 and 11 are provided for centering the door within passage 3 and to minimize or eliminate rubbing friction between the door and the walls of the passage. Guides 11 are positioned and configured to guide and center the door laterally, or in the y-direction, while guides 9 center the door front-to-back, or in the x-direction. The door guides may be mounted to the vertical surfaces of the door as shown, or alternatively to the top and bottom of the door. The door guides may comprise bearings, wheels, rollers, or simply blocks of a low friction material such as Teflon®. Preferably the guides have a sufficient degree of compliance, either through the choice of material used or through the mounting configuration, to accommodate dimensional tolerances or misalignment present between the door and passage. Vertical tracks 13 are preferably attached to the armor plating surfaces of passage 3 to provide a hard, smooth, and plumb surface for the door guides. Tracks 13 are preferably made of flat strips of high strength steel. For example in one embodiment tracks 13 are flat strips of 4130 alloy steel, roughly ½ by 4 inches in cross-section.
It should be noted however that any out of plane (x-direction) movement of the door, as for example in a door sealing operation, would tend to cause the side door guides 11 of the present embodiment to slide instead of roll, creating friction and wear of the rollers 30 and tracks 13. To avoid that, rollers 30 of door guides 11 are supported within a wide bracket 40 on a shaft 42 that is substantially longer than the roller, allowing the bracket and shaft to move forward and backward with the door while the roller 30 remains fixed in place against the wall of the passage. A spring 44 biases the roller 30 forward against the front side of bracket 40 during normal operation, ensuring a wide enough gap between the roller 30 and the other side of bracket 40 to accommodate forward door movement in a door sealing operation. Spring 44 is accordingly selected to be compressible with substantially less force than the friction force required to slide roller 30 on the wall of the passage 3.
In addition, because the door is supported atop the extendable cylinder 2, any forward, backward, or lateral door motion necessarily moves the upper end of cylinder 2 by the same amount. Thus, cylinder 2 is preferably designed in such a way to accommodate the motion of door 1 associated with a door sealing operation for example, without unduly inhibiting the door motion, and without the cylinder itself becoming damaged in the process. In one preferred embodiment, pivoting joints are employed at each end of cylinder 2, allowing the cylinder to freely tilt relative to the door 1 and the passage 3. The pivoting joints may be for example a simple hinge arrangement, providing two degrees of freedom, or more preferably a ball and socket design providing three degrees of freedom.
Pocket Door Configuration
Door 60 is preferably supported vertically in the pocket by a series of support rollers 74 disposed between the bottom of the door and the pocket base 80. The support rollers may be configured for example as wheels or as cylindrical rollers, and are preferably designed to carry the substantial weight of door 60. The door 60 is preferably guided within the pocket by compliant door guides 76 (see
As previously mentioned, a door sealing operation involves moving the door forward until the door physically seals against the rearward facing front wall 116 of the passage 3 or 61. To facilitate that movement in the present embodiment, the pocket door 60 may be supported by a second roller system. Referring to
Door Locks
Referring again to
Going from the locked condition of
The door locks of the present invention may in addition act to prevent in-plane (y-z) door motion when locked. A series of sockets 114 are defined in the back surface of door for receiving the lock bolts. Should there be a failure of the system that positions the door vertically or laterally within the passage, such as a loss of pressure in cylinder 2, the engagement of the lock bolts 106 in sockets 114 acts to secure the door and prevent in-plane movement or slipping. A taper 130 may be provided on at least one edge of bolt 106 where it engages socket 114. The taper 130 helps to ensure adequate alignment between bolts 106 and sockets 114, and prevent bolt 106 from binding or becoming lodged in socket 114. A shim stack 132 affixed to the end of bolt 106 as shown, or alternatively inside socket 114, may be incorporated to adjust the position of the door, and the compression of seal 104.
Although
Solid lines in
Door Seal
As mentioned above, the door is closed and sealed by forcing the door forward against door seal 104 in the front wall 116 of passage 3 or pocket 61. The door seal 104 is mounted in, or on the front wall around the opening to the threat side 5 of corridor 4, and may comprise any suitable flexible material such as metal strips, foam, o-rings, and the like. In one preferred embodiment depicted in
In one particularly preferred embodiment shown in
The o-rings may be secured into grooves 204 using barbed studs 208 mounted in the bottom of the grooves. The barbed studs allow for a blind installation whereby aligned holes in the back of the o-rings (not shown) are snapped over the barbed end of the studs by simply pushing the o-rings into the grooves. A worn o-ring may be conveniently replaced by pulling out the old o-ring and installing a new one without necessarily replacing the barbed studs 208 or carrier 201. Alternatively, the carrier and o-ring assembly may be replaced as a unit.
The door seal 104 may further include at least one conduit 210 with a first end in fluid communication with a sealed space 212 formed between o-ring seals 200. A second end of conduit 210 is preferably adapted for connection to external devices, such as a pump 218 and a pressure gauge 216. With the door closed, the quality of the seal can thus be inspected by pumping air into sealed space 212 with pump 218, and monitoring the bleed down rate using pressure gauge 216. Conduit 210 may additionally be utilized as a vent to prevent a vacuum condition in space 212 from trapping the door against the seal when the locks are disengaged. Alternatively if venting alone is insufficient, air may be pumped through conduit 210 into space 212 to positively break a vacuum condition.
Operation
The process of closing, latching, and sealing the high security door according to the present invention involves first translating the door within a passage or pocket from an open position in which corridor 4 is unblocked, to a closed position in which corridor 4 is blocked. For example the translating step may comprise moving the door vertically from an open position shown in
With the door translated into the closed position, but still centered in the passage, the bolts 106 of the upper and lower door locks 101 and 102 are driven forward against the back of door. The door locks may be configured such that the lower door bolts are driven into sockets 114, preventing further translational door movement, and supporting the door if necessary. Force applied to the door by the bolts pushes the door forward against the door seal 104, compressing the seal, and compressing door guides 9 or 76 on the front of the door against the front wall 116 of passage 3. The o-rings 200 expand in grooves 204 as the seal 104 compresses, allowing the door to continue moving forward until it abuts the back wall 116 if desired, sealing off corridor 4. A locking feature of the door locks braces the bolts against the back wall of the passage 3 to prevent any subsequent rearward motion of the door. The small forward and backward door movements associated with sealing and unsealing are accommodated by pivoting ends on cylinder 2 in a vertically moving door embodiment, or by a secondary roller system associated with the laterally moving pocket door embodiment.
Unlocking and opening the door involves first disengaging the locking feature and retracting the upper and lower door locks 101 and 102. The previously compressed door guides 9 on the front of the door extend under spring bias, forcing the door away from front wall 116 to a centered position in passage 3 or pocket 61. Any resistance due to a vacuum condition between o-ring seals 200 may be alleviated by venting or applying positive pressure to space 212 via conduits 210. Once the door is properly centered, and clear of seal 104, cylinder 2 or drive motor 63 may be operated to translate the door to an open position. In the case of a vertically moving door, the top of the door preferably doubles as a floor across the gap of passage 3 or pocket 61 with the door in the open position.
For the purposes of describing and defining the present invention it is noted that the use of relative terms, such as “substantially”, “generally”, “approximately”, and the like, are utilized herein to represent an inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. These terms are also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue.
Exemplary embodiments of the present invention are described above. No element, act, or instruction used in this description should be construed as important, necessary, critical, or essential to the invention unless explicitly described as such. Although only a few of the exemplary embodiments have been described in detail herein, those skilled in the art will readily appreciate that many modifications are possible in these exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the appended claims.
Patent | Priority | Assignee | Title |
10640940, | Dec 04 2017 | UNITED BARRIER TECHNOLOGIES, INC | Systems and methods for forming water barriers |
10954640, | Dec 04 2017 | UNITED BARRIER TECHNOLOGIES, INC | Systems for forming flood barriers |
11255121, | Jul 23 2015 | Hollow core door with perimeter air flow | |
11384496, | Dec 04 2017 | UNITED BARRIER TECHNOLOGIES, INC | Systems for forming flood barriers |
11746487, | Dec 04 2017 | UNITED BARRIER TECHNOLOGIES, INC | Systems for forming flood barriers |
Patent | Priority | Assignee | Title |
2552515, | |||
3714737, | |||
3969563, | Jun 01 1965 | Protective wall structure | |
4178859, | Sep 03 1976 | Bochumer Eisenhutte Heintzmann GmbH & Co. | Door-like closure |
4577577, | May 27 1983 | Oy Wartsila AB | Sliding door arrangement |
4716683, | May 13 1985 | Pella Corporation | Door weatherstripping assembly |
4720936, | Nov 07 1986 | REESE ENTERPRISES, INC D B A ASTRO PLASTICS | Extruded weather strip structure |
4727789, | Jun 24 1986 | ALLIANT TECHSYSTEMS, INC GES | Vented suppressive shielding |
4935989, | May 05 1988 | Pneumatic door closer with sustained closing force during closure | |
5060582, | Oct 20 1989 | Salzer Sicherheitstechnik GmbH | High security blast resistant door leaf |
5231935, | Dec 31 1991 | STAR BANK, NATIONAL ASSOCIATION | Vault door |
5491992, | Apr 29 1994 | King pin locking mechanism | |
5660021, | Sep 17 1994 | TRUSSBILT, LLC A MN LIMITED LIABILITY COMPANY | Security of buildings and other structures |
5873205, | Nov 28 1990 | ADVANTAGE OFFICE SYSTEMS, L L C | Privacy panel for use with open office furniture systems |
5911763, | Jan 12 1998 | CGI WINDOWS AND DOORS, INC | Three point lock mechanism |
5983578, | Nov 19 1997 | Arizona Public Service Company | Penetration-resistant security passway and door therefor |
6209264, | Jan 06 1999 | RAY PROOF LIMITED | Device for supporting and moving a door in a multitude of positions |
6240858, | May 27 1997 | Penetration resistant panel | |
6338594, | Nov 20 1998 | ADLER, RICHARD S | Movable barrier wall |
6514011, | Dec 22 1999 | NOMURA 4CS CORP , LTD ; NANSEI CORPORATION | Movable water-protection apparatus |
6623210, | Jan 31 2001 | NOMURA 4CS CORP , LTD ; NANSEI CORPORATION | Guidance method and guidance system of flood water |
6732479, | Dec 27 2000 | NOMURA 4CS CORP , LTD ; NANSEI CORPORATION | Movable defensive apparatus |
6758504, | Aug 30 2002 | Electromagnetic door lock | |
6883440, | Dec 31 2003 | Safe | |
7000550, | May 03 2004 | Ablative blast resistant security door panel | |
7114594, | Sep 29 2003 | Inventio AG | Door frame of a shaft door with a control arrangement for an elevator shaft and method for access to a control unit |
7328934, | Jun 17 2005 | Mitsuba Corporation | Sliding door opening and closing device |
7341549, | Feb 11 2005 | Deckel Maho Pfronten GmbH | Device for gripping and holding a component |
Executed on | Assignor | Assignee | Conveyance | Frame | Reel | Doc |
Jan 14 2011 | Armorworks Enterprises LLC | (assignment on the face of the patent) | / | |||
Jun 30 2017 | ARMORWORKS ENTERPRISES, INC | THE PRIVATEBANK AND TRUST COMPANY | SECURITY INTEREST SEE DOCUMENT FOR DETAILS | 043830 | /0237 | |
Mar 12 2024 | ARMORWORKS ENTERPRISES, INC | UMPQUA BANK | SECURITY INTEREST SEE DOCUMENT FOR DETAILS | 067398 | /0330 |
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